SPARTA (7 Jul 2014)
# advect particles via VSS collisional flow on a uniform grid
# particles reflect off global box boundaries

variable            x index 10
variable            y index 10
variable            z index 10

variable            lx equal $x*1.0e-5
variable            lx equal 100*1.0e-5
variable            ly equal $y*1.0e-5
variable            ly equal 100*1.0e-5
variable            lz equal $z*1.0e-5
variable            lz equal 100*1.0e-5

variable            n equal 10*$x*$y*$z
variable            n equal 10*100*$y*$z
variable            n equal 10*100*100*$z
variable            n equal 10*100*100*100

seed	    	    12345
dimension   	    3
global              gridcut 1.0e-5

boundary	    rr rr rr

create_box  	    0 ${lx} 0 ${ly} 0 ${lz}
create_box  	    0 0.001 0 ${ly} 0 ${lz}
create_box  	    0 0.001 0 0.001 0 ${lz}
create_box  	    0 0.001 0 0.001 0 0.001
Created orthogonal box = (0 0 0) to (0.001 0.001 0.001)
create_grid 	    $x $y $z
create_grid 	    100 $y $z
create_grid 	    100 100 $z
create_grid 	    100 100 100
Created 1000000 child grid cells
  parent cells = 1
  CPU time = 0.033556 secs
  create/ghost percent = 66.611 33.389

balance_grid        rcb part
Balance grid migrated 875000 cells
  CPU time = 2.0764 secs
  reassign/sort/migrate/ghost percent = 3.59806 0.169284 79.8893 16.3434

species		    ar.species Ar
mixture		    air Ar vstream 0.0 0.0 0.0 temp 273.15

global              nrho 7.07043E22
global              fnum 7.07043E6

collide		    vss air ar.vss

create_particles    air n $n
create_particles    air n 10000000
Created 10000000 particles
  CPU time = 0.2567 secs

stats		    10
compute             temp temp
stats_style	    step cpu np nattempt ncoll c_temp

# first equilibrate with large timestep to unsort particles
# then benchmark with normal timestep

timestep 	    7.00E-8
run                 30
Memory usage per proc in Mbytes:
  particles (ave,min,max) = 128.746 128.746 128.746
  grid      (ave,min,max) = 25.1771 25.1771 25.1771
  surf      (ave,min,max) = 0 0 0
  total     (ave,min,max) = 153.923 153.923 153.923
Step CPU Np Natt Ncoll temp 
       0            0 10000000        0        0    273.16859 
      10    10.823001 10000000  9631905  7044788    273.16859 
      20    22.748964 10000000  9894380  7055249    273.16859 
      30    34.820402 10000000 10034185  7064328    273.16859 
Loop time of 34.8204 on 8 procs for 30 steps with 10000000 particles

Particle moves    = 300000000 (300M)
Cells touched     = 1486869246 (1.49B)
Particle comms    = 11865808 (11.9M)
Boundary collides = 11989583 (12M)
Boundary exits    = 0 (0K)
SurfColl checks   = 0 (0K)
SurfColl occurs   = 0 (0K)
Collide attempts  = 290479156 (290M)
Collide occurs    = 210896284 (211M)
Particles stuck   = 0

Particle-moves/CPUsec/proc: 1.07695e+06
Particle-moves/step: 1e+07
Cell-touches/particle/step: 4.95623
Particle comm iterations/step: 3
Particle fraction communicated: 0.0395527
Particle fraction colliding with boundary: 0.0399653
Particle fraction exiting boundary: 0
Surface-checks/particle/step: 0
Surface-collisions/particle/step: 0
Collision-attempts/particle/step: 0.968264
Collisions/particle/step: 0.702988

Move  time (%) = 21.0788 (60.5357)
Coll  time (%) = 11.1014 (31.8817)
Sort  time (%) = 2.51424 (7.22059)
Comm  time (%) = 0.000325382 (0.000934456)
Outpt time (%) = 0.125647 (0.360843)
Other time (%) = 6.4373e-05 (0.000184871)

Particles: 1.25e+06 ave 1.25198e+06 max 1.24877e+06 min
Histogram: 2 0 1 1 2 1 0 0 0 1
Cells:      125000 ave 125000 max 125000 min
Histogram: 8 0 0 0 0 0 0 0 0 0
GhostCell: 15608 ave 15608 max 15608 min
Histogram: 8 0 0 0 0 0 0 0 0 0
EmptyCell: 7957 ave 7957 max 7957 min
Histogram: 8 0 0 0 0 0 0 0 0 0
timestep 	    7.00E-9
run 		    100
Memory usage per proc in Mbytes:
  particles (ave,min,max) = 129.776 129.776 129.776
  grid      (ave,min,max) = 25.1771 25.1771 25.1771
  surf      (ave,min,max) = 0 0 0
  total     (ave,min,max) = 154.953 154.953 154.953
Step CPU Np Natt Ncoll temp 
      30            0 10000000 10034185  7064328    273.16859 
      40     3.652467 10000000   903234   704845    273.16859 
      50     7.341768 10000000   918863   705860    273.16859 
      60    11.050607 10000000   929582   704968    273.16859 
      70    14.768657 10000000   938861   705027    273.16859 
      80    18.481151 10000000   947435   705291    273.16859 
      90    22.201895 10000000   953798   705577    273.16859 
     100    25.926723 10000000   958806   705289    273.16859 
     110    29.675865 10000000   964271   706099    273.16859 
     120    33.395293 10000000   968032   705296    273.16859 
     130    37.137535 10000000   972321   706274    273.16859 
Loop time of 37.1376 on 8 procs for 100 steps with 10000000 particles

Particle moves    = 1000000000 (1B)
Cells touched     = 1395637258 (1.4B)
Particle comms    = 3991339 (3.99M)
Boundary collides = 3997548 (4M)
Boundary exits    = 0 (0K)
SurfColl checks   = 0 (0K)
SurfColl occurs   = 0 (0K)
Collide attempts  = 93688408 (93.7M)
Collide occurs    = 70170037 (70.2M)
Particles stuck   = 0

Particle-moves/CPUsec/proc: 3.36586e+06
Particle-moves/step: 1e+07
Cell-touches/particle/step: 1.39564
Particle comm iterations/step: 1
Particle fraction communicated: 0.00399134
Particle fraction colliding with boundary: 0.00399755
Particle fraction exiting boundary: 0
Surface-checks/particle/step: 0
Surface-collisions/particle/step: 0
Collision-attempts/particle/step: 0.0936884
Collisions/particle/step: 0.07017

Move  time (%) = 16.8907 (45.4814)
Coll  time (%) = 12.4509 (33.5264)
Sort  time (%) = 7.25391 (19.5325)
Comm  time (%) = 0.172653 (0.4649)
Outpt time (%) = 0.369243 (0.994258)
Other time (%) = 0.000198543 (0.000534615)

Particles: 1.25e+06 ave 1.25384e+06 max 1.24834e+06 min
Histogram: 2 2 1 1 0 1 0 0 0 1
Cells:      125000 ave 125000 max 125000 min
Histogram: 8 0 0 0 0 0 0 0 0 0
GhostCell: 15608 ave 15608 max 15608 min
Histogram: 8 0 0 0 0 0 0 0 0 0
EmptyCell: 7957 ave 7957 max 7957 min
Histogram: 8 0 0 0 0 0 0 0 0 0

